Characterization and expression analysis of genes encoding Taxol biosynthetic enzymes in Taxus spp.

Abstract

Taxol (Paclitaxel), an important anticancer drug, is derived at very low yields from Taxus (yew) species that grow very slowly. In the present study, thirteen genes that encode enzymes involved in Taxol biosynthesis in Taxus spp. were analyzed with bioinformatics methods, and their expression levels in different tissues and after cold and hormone treatments were also analyzed. The results indicated that many cis-elements related to abiotic stresses and hormones were found in the promoter sequences of the 8 genes involved in Taxol biosynthesis. Moreover, the 13 enzymes encoded by the target genes were located in different organelles and had many phosphorylation sites in the response proteins. The 13 genes were expressed highly either in roots or in stems, with lower transcripts in needles, and they were highly expressed after treatment with cold, gibberellin, methyl jasmonate or coronatine, consistent with predictions based on the bioinformatics analysis. These results suggest that the factors such as hormones and abiotic stresses stimulate taxane biosynthesis in yews, providing an important way to sustainably generate taxanes from yew trees or their cell cultures to improve Taxol yields.